1. Field of the Invention
The invention relates to a tuning device and particularly relates to a tuning device that produces a sound (i.e. reference sound) of a pitch (i.e. reference pitch, which serves as the reference) of a reference pitch name as the tuning target and allows the user to check the pitch of a sound that is to be tuned from a mixture sound of the reference sound and the sound that is to be tuned.
2. Description of Related Art
A traditional tuning device cannot be used to carry out tuning for matching the pitch of the sound that is to be tuned, e.g. a vocal sound or a sound of a wind instrument such as a flute, while the reference sound is produced through a loudspeaker. The reason is that, when the loudspeaker outputs the reference sound, the tuning device may misidentify the reference sound it produces as the sound that is to be tuned and detect the wrong pitch, and as a result, fail to detect the pitch of the sound that is to be tuned. For this reason, the user first confines the reference sound produced via the loudspeaker by ear, and then stops the reference sound and inputs the sound that is to be tuned to the tuning device, so as to perform the tuning. However, for such a method, the user needs to listen to and remember the reference pitch so as to perform the tuning, which is rather difficult.
Regarding this, Patent Literature 1 discloses an electronic tuner that uses a mixture circuit to mix an audio signal of the sound that is to be tuned, which is inputted via an input terminal, with a reference sound signal (equivalent to the reference sound signal of Patent Literature 1), and outputs the mixture through headphones via an output terminal when the sound that is to be tuned, which is inputted via the input terminal, is inputted to a tuning circuit. With the electronic tuner of Patent Literature 1, the user can produce the sound that is to be tuned and perform the tuning while the user listens to the reference sound (equivalent to the reference sound of Patent Literature 1) through headphones to check the pitch of the reference sound.
In addition, Patent Literature 2 discloses a polyphonic tuner that has a pitch detector for simultaneously detecting several pitches.